linux-toradex.git/fs/nfs/client.c, branch v3.10.85

NFSv4.1: Set the RPC_CLNT_CREATE_INFINITE_SLOTS flag for NFSv4.1 transports

2013-04-14T16:59:28+00:00

This ensures that the RPC layer doesn't override the NFS session
negotiation.

Signed-off-by: Trond Myklebust

nfs: idr_destroy() no longer needs idr_remove_all()

2013-02-28T03:10:14+00:00

idr_destroy() can destroy idr by itself and idr_remove_all() is being
deprecated.  Drop reference to idr_remove_all().  Note that the code
wasn't completely correct before because idr_remove() on all entries
doesn't necessarily release all idr_layers which could lead to memory
leak.

Signed-off-by: Tejun Heo 
Cc: "J. Bruce Fields" 
Cc: Trond Myklebust 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

NFS: avoid NULL dereference in nfs_destroy_server

2012-12-13T04:55:56+00:00

In rare circumstances, nfs_clone_server() of a v2 or v3 server can get
an error between setting server->destory (to nfs_destroy_server), and
calling nfs_start_lockd (which will set server->nlm_host).

If this happens, nfs_clone_server will call nfs_free_server which
will call nfs_destroy_server and thence nlmclnt_done(NULL).  This
causes the NULL to be dereferenced.

So add a guard to only call nlmclnt_done() if ->nlm_host is not NULL.

The other guards there are irrelevant as nlm_host can only be non-NULL
if one of these flags are set - so remove those tests.  (Thanks to Trond
for this suggestion).

This is suitable for any stable kernel since 2.6.25.

Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown 
Signed-off-by: Trond Myklebust

NFS: Get rid of unnecessary asserts

2012-11-04T19:43:38+00:00

If the nfs_client fails to initialise correctly, then it will
return an error condition.

Signed-off-by: Trond Myklebust

NFS: Remove unnecessary semicolons (fs/nfs/client.c)

2012-10-01T22:40:03+00:00

There are some unnecessary semicolons in function find_nfs_version. Just remove them.

Signed-off-by: Yanchuan Nian 
Signed-off-by: Trond Myklebust

NFS41: fix error of setting blocklayoutdriver

2012-10-01T22:37:39+00:00

After commit e38eb650 (NFS: set_pnfs_layoutdriver() from
nfs4_proc_fsinfo()), set_pnfs_layoutdriver() is called inside
nfs4_proc_fsinfo(), but pnfs_blksize is not set. It causes setting
blocklayoutdriver failure and pnfsblock mount failure.

Cc: stable  [since v3.5]
Signed-off-by: Peng Tao 
Signed-off-by: Trond Myklebust

NFS: Discover NFSv4 server trunking when mounting

2012-10-01T22:33:33+00:00

"Server trunking" is a fancy named for a multi-homed NFS server.
Trunking might occur if a client sends NFS requests for a single
workload to multiple network interfaces on the same server.  There
are some implications for NFSv4 state management that make it useful
for a client to know if a single NFSv4 server instance is
multi-homed.  (Note this is only a consideration for NFSv4, not for
legacy versions of NFS, which are stateless).

If a client cares about server trunking, no NFSv4 operations can
proceed until that client determines who it is talking to.  Thus
server IP trunking discovery must be done when the client first
encounters an unfamiliar server IP address.

The nfs_get_client() function walks the nfs_client_list and matches
on server IP address.  The outcome of that walk tells us immediately
if we have an unfamiliar server IP address.  It invokes
nfs_init_client() in this case.  Thus, nfs4_init_client() is a good
spot to perform trunking discovery.

Discovery requires a client to establish a fresh client ID, so our
client will now send SETCLIENTID or EXCHANGE_ID as the first NFS
operation after a successful ping, rather than waiting for an
application to perform an operation that requires NFSv4 state.

The exact process for detecting trunking is different for NFSv4.0 and
NFSv4.1, so a minorversion-specific init_client callout method is
introduced.

CLID_INUSE recovery is important for the trunking discovery process.
CLID_INUSE is a sign the server recognizes the client's nfs_client_id4
id string, but the client is using the wrong principal this time for
the SETCLIENTID operation.  The SETCLIENTID must be retried with a
series of different principals until one works, and then the rest of
trunking discovery can proceed.

Signed-off-by: Chuck Lever 
Signed-off-by: Trond Myklebust

NFS: Introduce "migration" mount option

2012-10-01T22:33:33+00:00

Currently, the Linux client uses a unique nfs_client_id4.id string
when identifying itself to distinct NFS servers.

To support transparent state migration, the Linux client will have to
use the same nfs_client_id4 string for all servers it communicates
with (also known as the "uniform client string" approach).  Otherwise
NFS servers can not recognize that open and lock state need to be
merged after a file system transition.

Unfortunately, there are some NFSv4.0 servers currently in the field
that do not tolerate the uniform client string approach.

Thus, by default, our NFSv4.0 mounts will continue to use the current
approach, and we introduce a mount option that switches them to use
the uniform model.  Client administrators must identify which servers
can be mounted with this option.  Eventually most NFSv4.0 servers will
be able to handle the uniform approach, and we can change the default.

The first mount of a server controls the behavior for all subsequent
mounts for the lifetime of that set of mounts of that server.  After
the last mount of that server is gone, the client erases the data
structure that tracks the lease.  A subsequent lease may then honor
a different "migration" setting.

This patch adds only the infrastructure for parsing the new mount
option.  Support for uniform client strings is added in a subsequent
patch.

Signed-off-by: Chuck Lever 
Signed-off-by: Trond Myklebust

SUNRPC: Introduce rpc_clone_client_set_auth()

2012-10-01T22:33:33+00:00

An ULP is supposed to be able to replace a GSS rpc_auth object with
another GSS rpc_auth object using rpcauth_create().  However,
rpcauth_create() in 3.5 reliably fails with -EEXIST in this case.
This is because when gss_create() attempts to create the upcall pipes,
sometimes they are already there.  For example if a pipe FS mount
event occurs, or a previous GSS flavor was in use for this rpc_clnt.

It turns out that's not the only problem here.  While working on a
fix for the above problem, we noticed that replacing an rpc_clnt's
rpc_auth is not safe, since dereferencing the cl_auth field is not
protected in any way.

So we're deprecating the ability of rpcauth_create() to switch an
rpc_clnt's security flavor during normal operation.  Instead, let's
add a fresh API that clones an rpc_clnt and gives the clone a new
flavor before it's used.

This makes immediate use of the new __rpc_clone_client() helper.

This can be used in a similar fashion to rpcauth_create() when a
client is hunting for the correct security flavor.  Instead of
replacing an rpc_clnt's security flavor in a loop, the ULP replaces
the whole rpc_clnt.

To fix the -EEXIST problem, any ULP logic that relies on replacing
an rpc_clnt's rpc_auth with rpcauth_create() must be changed to use
this API instead.

Signed-off-by: Chuck Lever 
Signed-off-by: Trond Myklebust

NFS: Fix a regression when loading the NFS v4 module

2012-08-16T20:15:49+00:00

Some systems have a modprobe.d/nfs.conf file that sets an nfs4 alias
pointing to nfs.ko, rather than nfs4.ko.  This can prevent the v4 module
from loading on mount, since the kernel sees that something named "nfs4"
has already been loaded.  To work around this, I've renamed the modules
to "nfsv2.ko" "nfsv3.ko" and "nfsv4.ko".

I also had to move the nfs4_fs_type back to nfs.ko to ensure that `mount
-t nfs4` still works.

Signed-off-by: Bryan Schumaker 
Signed-off-by: Trond Myklebust